// const { defineConfig } = require('@vue/cli-service')
const path = require('path')
function resolve(dir) {
  return path.join(__dirname, dir)
}
module.exports = {
  // transpileDependencies: true,
  lintOnSave: false,
  publicPath: '/',
  outputDir: 'dist',
  assetsDir: 'static',
  productionSourceMap: false,
  devServer: {
    port: 8080,
    open: true,
    hot: true,
    host: '127.0.0.1',
    // overlay: {
    //   warnings: false,
    //   errors: true,
    // },
  },
  configureWebpack: {
    resolve: {
      fallback: { path: require.resolve('path-browserify') },
      alias: {
        '@': resolve('src'),
      },
    },
  },
  chainWebpack(config) {
    // it can improve the speed of the first screen, it is recommended to turn on preload
    // it can improve the speed of the first screen, it is recommended to turn on preload
    // config.plugin('preload').tap(() => [
    //   {
    //     rel: 'preload',
    //     // to ignore runtime.js
    //     // https://github.com/vuejs/vue-cli/blob/dev/packages/@vue/cli-service/lib/config/app.js#L171
    //     fileBlacklist: [/\.map$/, /hot-update\.js$/, /runtime\..*\.js$/],
    //     include: 'initial',
    //   },
    // ])

    // when there are many pages, it will cause too many meaningless requests
    config.plugins.delete('prefetch')

    // set svg-sprite-loader
    config.module.rule('svg').exclude.add(resolve('src/icons')).end()
    config.module
      .rule('icons')
      .test(/\.svg$/)
      .include.add(resolve('src/icons'))
      .end()
      .use('svg-sprite-loader')
      .loader('svg-sprite-loader')
      .options({
        symbolId: 'icon-[name]',
      })
      .end()

    config.when(process.env.NODE_ENV !== 'development', (config) => {
      config
        .plugin('ScriptExtHtmlWebpackPlugin')
        .after('html')
        .use('script-ext-html-webpack-plugin', [
          {
            // `runtime` must same as runtimeChunk name. default is `runtime`
            inline: /runtime\..*\.js$/,
          },
        ])
        .end()
      config.optimization.splitChunks({
        chunks: 'all',
        cacheGroups: {
          libs: {
            name: 'chunk-libs',
            test: /[\\/]node_modules[\\/]/,
            priority: 10,
            chunks: 'initial', // only package third parties that are initially dependent
          },
          elementUI: {
            name: 'chunk-elementUI', // split elementUI into a single package
            priority: 20, // the weight needs to be larger than libs and app or it will be packaged into libs or app
            test: /[\\/]node_modules[\\/]_?element-ui(.*)/, // in order to adapt to cnpm
          },
          commons: {
            name: 'chunk-commons',
            test: resolve('src/components'), // can customize your rules
            minChunks: 3, //  minimum common number
            priority: 5,
            reuseExistingChunk: true,
          },
        },
      })
      // https:// webpack.js.org/configuration/optimization/#optimizationruntimechunk
      config.optimization.runtimeChunk('single')
    })
  },
}
